Manual mode does not work

Hello, what testing has been performed? Testing is the only thing that can determine what is wrong with your manual shifters. It's frustrating because you spend all that money and time and effort, but a little money and time and effort could be better directed by either paying a technician who knows what to check and how, and has the diagnostic equipment to do so, or to invest in the tooling yourself If desired. I would use a diagnostic tool to monitor function of the shifters, and if it's showing they are working but there is no response, you can look further to determine if the signal is getting to the transmission or not.